The relationship between environmental and genetic factors in the regulation of alcohol consumption, while often cited as important, are not well understood. While a number of studies have examined the effects of various environmental factors on alcohol consumption, only a few of these have attempted to determine how these factors might interact with genetic factors. During the last grant period, we have found that several behavioral factors can impact ethanol consumption and that several of these factors interact with each other. Depending on the type of introduction (initiation) to alcohol, the amount, concentration, and cost of the ethanol and time/day it is available all effect intake. The most important finding has been that intake appears to be mostly regulated by the number of discrete drinking bouts which occur during a day and not by the size of these individual bouts. This appears true for both nonselected rats as well as for both the Indiana P and NP rat. The proposed studies will expand on these studies by examining the effects of initiation and an environmental variable upon drinking patterns of several lines of rats. By using the same behavioral procedure, in the same laboratory across several lines of selectively bred animals who differ in their alcohol preference, we hope to be able to address the question of the interaction between these genetic selections and environmental factors which are known to impact ethanol consumption. An additional set of studies is proposed to continue to explore added models of drinking initiation, with the goal of providing other models of alcohol self-administration which may better resemble excessive drinking patterns.